Railway car retarder



Patented Sept. 6, 1932 i atraen gPia-TEN"` JoHN W. LIVINGSTON, or WILKINSBURG, PNN'SYLVANIA, assrGNon rro rita UNroN o SWITCH a SIGNAL COMPANY, or swrssvALE, PENNsYLVaNra, A CORPORATION.

OF PENNSYLVANIA RAILWAY CAR .RETARDER Application led September 2, 1931. Serial No. 560,718.`

My invention relates to railway car lretardl ers, and particularly to car retarders of the track brake type used in classification or hump yards of railroads for controlling the speed of cars.

One obj-ect of my invention is the provision oit improved automatic apparatus for controlling the braking action of acar retarder of the type described in accordance with the speed of cars approaching or passingthrough the retarder. Speciiically, the present invention is an improvement on apparatus'of the type disclosed and claimed in an application for Letters Patent of the United States, led by Herbert L. Bone on July 9, 1931, Serial No. 549,588, for railway braking apparatus. l l will describe one form of car retarder' controlling apparatus embodying my invention, and will then po-int out the novel features thereof in claims.

The accompanying drawing is a view, partially sectioned and partially diagrammatic, illustrating one form of apparatus embodying my invention. y

Referring to the drawing, the reference characters 1 and ladesignate the track rails ot a stretch of railway track over which cars normally move in the direction indicated by the arrow under such conditions that it is tents, and the condition of the car*l as to' whether it is a free running car or otherwise.

In order to `control the speed of the cars,

the stretch 'of track illustrated in the drawing is provided with `a Car retarder R which, in the form here shown, comprises two braking bars 2 and 3, extending parallel with and located on opposite sides of rail 1, and two similar braking bars 2a and 3a extending parallel with, and located on opposite sides ofrailla,

The braking bars 2, 3, 22 and@a are oper# ated by a fluid pressure motor M comprising a cylinder 4 containing a reciprocable .piston 5 attached to one end of a piston rod 6. 'The braking bars 2, 3, 2a and 3' are operatively connected with the'pistonrod 6 through suitable linkwork includingy a bell crank 7' and a lever 8 pivotally supported at pointf9. When piston 5 occupies itsextreme righthand position, in which it is'l illustrated in the drawing, the braking bars occupy their non-braking or ineiiective positions in which f they are out ot engagement with the wheels of aecar traversing rails 1 and la." When piston 5 is moved to its left-hand position,

however, as whentluid pressure is admitted to the right-hand end offcylinder 4, the brak# ing lbars 2, 3, 2i and l'are moved' toward the associatedrail'to theirfeiiective or braking positions in which they will engage thewheels` of a cartraversing the rails 1 and 12, toretard the speed of the car. 1

The motorM is controlled .by twoimagnet valves V1 and V2, each comprising a valve Vstem 1() biased to an upper position by means of a spring 11, and each providedfwitha winding 12 and an armatureV 13. W hen wind-V ing 12 of valve V1 is deenergized, as shown Vin the drawing, valve stem 10 of this valvel is moved to its upperposition by the spring 11, and under these conditions',"the right-hand end 'of cylinder 4 Vis connectedfwith atmosphere through a pipe 14 and a port 15.-y When winding 12 of this valve is energized, however, valve stem 10 lis -m`oved downwardly aga-instthe bias of spring 11 to disconnect pipe 14 from atmosphere, and to connect this pipe with a suitable source offiiuid pressure, usually air, Vthrough a pipe 16. -When wind ing 12 ofvalve V1 Vis energized, therefore, the Huid pressure supplied to the right-hand end of cylinder 4'moves piston 5 toward-'the left, thereby moving the Vbraking 'bars to their effective or braking positions. 1 f

When Ywinding 12 of valve V2 is deenei gized, valve stem 10 of thisvalve is moved toits upper position, and the lefthand end of cylinder 4 is then connected with atmosphere through a pipe 17and a port 18. When.,y 100 winding 12 of valve V2 is energized, however,

as shown in the drawing, valve stein is moved downwardly, disconnecting pipe 17 from port 18, and connecting pipe 17 with pipe 16. It will be apparent, therefore, that when valve V2 is energized, piston 5 is urged toward the right, thus holding the braking bars in their ineffective or non-braking posi tions. Y Y f The magnet Vvalves V1. and V2 are controlled by means of a normally deenergized controlz relay C, and by a manually operableV lever L. The lever L, in the form here shown., capable of assuming a left-hand position a,

in which it is illustrated in the drawing, and

aright-hand position `VI), indicated by a dotted line in the drawing. Cperatively connected with the lever'L .isr a contact arm 19V which engages a fixed contact 3192 or 19bto closea contact 19-192/or 19---19b according as lever L occupies: its a or b position.

Winding 12 ofvalve V2 is provided with a circuiti which Vpasses from a suitable source of current, here-*shown as a battery 20, through wire 21, winding 12 of valve V2, wire 22, contact 19--19EL 'of'lever L, wire 23, back contact 22l-24b ofrelayV C, and wire 25 back to battery 20.. Winding 12 of valve V2 is also provided with another circuit which-isi similar to the circuit just tracedwith the exception that this circuit includes a wire 26 anda fre-nt contact-24i--2lla of relay C, instead 'of con-` Y tact 19'-192of lever'L, wire 23, and back con- Y a circuit which passes fromv battery 20,v

through wire 2'1, winding 12 of valvey V1, Wire 27, contact'19-192of` lever L, wire'23,

'back contact 24-24b`ofrelay'C, and' wire 25' back to battery 20. It will be apparent, therefore, that Winding12 of valve V1 will be enenV gized when'and only when lever L occupies itsv b' position and relay C is deenergized.

It'follws from the foregoing that when reev lay` C is deenergized, the braking bars willV occupy their non-braking orA brakiner positionsaecording as lever L occupies its a' or b position, but that, when relay C becomes energized, if the braking bars do not already occupy. their non-braking positions, they will automaticallybe moved to their non-braking positions. p

The apparatus also includes a series'of contacts 292,' 29h, 29, 29d, 29e and 29f, a series l of timing relays S2, Sb, S2, Sd and Se,fand aseriesof locking relays T2, T,Tc, ',Ild a-nd Te. In the particular embodiment of the in.

i vention illustrated in the drawing, .the confactsl 29, 29D, 29, 29d, 29ev and 292 arecontrolledV byV means of treadles '28, 28,2., 282,` 282,'V

-treadles may be of the usual spring biased type; and eachreturns to itsnormal position after being'depressed by a car Wheel. Each y Contact is operatively connected with the as- Y sociated treadle in such manner that when the treadle is' not depressed, the contact will be closed, but that, when the treadle becomes depressed by a car wheel, the contact will become opened, and will subsequently remain open during theentire time the treadle is depressed. It will be' apparent, therefore, vthat when a car' wheel is passing one of the treadles, the associated contact rwill be held open for a time interval which depends upon c the lengthof the treadlel and the speed of the Y car. The lengths of the treadles-will usually be the samev andmaybe varied as conditions require, butthe lengths of the treadles and lthe spacing between them 'will preferably be such that the distance from the entering end of one 5 treadle to the leaving end of the treadle next in advance will be less than the distance between adjacent carl wheels in thev same car truck; and the distance' from the leaving end of one treadle tothe entering end of the second treadle inadvance will be greater than the distance between adjacent cari-wheels in the; same car truck. It will be seen, therefore, that4 two adjacent treadles will not'becorne depressed at one time, or that one treadle and the second treadle in advance will not becomedepressed` at one-time.

. The timingA relays S2, Sb, SC, Sd andSe are si-niilarfrelays, and, as here shown, have-slow releasing characteristics. Each of these relays isl connected with a pair of line wires 30 and l31 over an associated one of the contacts 29, as will be apparent from an inspection of the drawing, andthe line wires 30 and 31, in turn, are connected, through a rheostat D, wth a suitable source of electromotive force, here Yshown as a battery B. It will be apparent, therefore, that when none of the treadles 28 isy depressed, as will be: the` case.

when no car is traversing the stretch of track shown in the dra-wingall of these relays will be energized; but that, when a `car istraversingthe stretch of track shown in the drawing, each timea wheel of the car depresses one oi thetreadles 28, the associated relay S will become de'energizedlfor an interval of time which depends upon the speed of the car.

If'the speed of the car is sufficiently slow so thatjthis time interval'is longer than the release time of such relay S, this relay will close its back contact 33, but if the car speed .is

not suiiiciently slow so thatthis time interval is longer than the release 'time of this relay, this-.relaywill not close its backcontact The relays S are so constructed that their 1.

eff

release times may be varied by varying the electromotive force impressed thereon, and it follows that, by causing the arm 33 of rheostat D to engage different taps, the car speed at which the relays S will close their back contacts may be varied; this speed being decreased as the arm v33 of rheostat D is moved toward the left, there being as many diiferent speeds as there are taps on the rheostat D. As will be explained more fully hereinafter, when the contact. 33 ofany one of the relays S becomes closed, the force applied to the braking bars of the car retarder to hold them in their braking positions is cut off, and it will be seen, therefore, that the rheostat D functions as a speed controller. The parts will usually be so proportioned that when all of the resistance of rheostat D r is cutout, t-he relays S will release when the associated treadles are depressed by the wheels of a car which is travelling at the slowest speed at which it is desired to have cars leave the retarder. 1

The locking relays T, Tb, T", Td and Te are ordinary quick acting relays, and are each' controlled by an associated one of the timing relays S and by one of the contacts 29. Referring 'to relay T, for example, this relay is provided with a pick-up circuit which passes from battery B through line wire 35, the winding of relay Ta, back contact 33 of relay Sa, and line wire 34'back to battery B. Relay Ta is also provided with a stick circuit which passes from battery B through line wire 35, the winding of relay T, front contact 36 of relay Ta, Contact 29C, and vline wire 30 back to battery B. It will'be apparent, therefore, that' when relay Sa be# comes, deenergized and closes .its back contact 33, 'relay Ta will become energized and will close its front contacts 36 and V37. If contact 29C is then closed as will normally be the case, the stick circuit for relay Ta will be closed, and this relay will therefore remain energized after Contact 33 opens until a car wheel ysubsequently depresses treadle 28C to open contact 29C, at-which time this relay will again become deenergized. Each of the other relays T is provided with circuits which are similar to the circuits just described for relay Ta. These circuits will be readily understood from an inspection of the drawing without describing them in detail. Y

.The relays Tvco'ntrol relay C by virtue of a plurality of parallel pick-up circuits, each of which includes a suitable source of current, here shown as a battery E, and the front contact 37 of a different one of the relays T. It will be seen, therefore, that whenl As shown, in the'drawing, all parts of the ing'ztThat is to say, the timing relays S are all energized, and the lock-ing relays T are all deenergized. -Arm 38oflrheostat Doccupies lthe position inwhich all of. the` resistance of the rheostat is cut'in. Relay C is deenergized. Lever L occupies its aposition, and the braking bars are therefore-heldin non-breakingpositions.

In explaining the` operation of the'apparatus as a whole, I williirst assume that the operator has moved the braking bars to their braking positions by moving lever, L from its a to its Y) position, that arm'381of rheostat :D hasv been 'movedl to a positionl which will cause the relays S to releaseyat some predetermined speed which I shall term control speed, and that a car moving lin the direction of theV arrowat :aLspeed which is less than control speed, traverse the stretch of track shown in :the drawing. Since the car is travelling at a speed which isl'ess than control speed, whenvthe first wheel' of the car passes treadle 28a, contact E29EL willbe held open for an interval of time which is .longer than the release time of the relays S under these conditions. Relay 1S will 1therefore close its backcontact 33. As a result, relay Ta will become energized and will 'close its front contacts and 37. The closing of front contact-36 of relayV Ta will complete the stick circuit for this relay, and relay Ta will therefore remain energized afteryrelay S'LL .again becomes. energized andopens its A so that' this `latter relay :willrernainv ener-V gized after relay Sbagain becomes energized.`

Furthermore, the energizationl of relay Tb will complete anothernci'rcuitlfor'relay 0,*

butsince relay C is already energized, it will not be affected, and the braking bars will therefore remain intheir non-braking posi-` tions.

Likewise, lwhen the lirst wheel of the car passes treadle 28C, a similar series of actions will take place. In addition, however, as soon as Contact 29 becomes opened, the Astick circuit' for relay T2L which' was pr'eviersly.

closedat this Contact will become interrupted, and relay T? will thereforenow become deenerg'ized.' The vdeenergization of relay'Ta will interrupt: the circuit which was` previllt ously closed forrelay Cat Vfront-contact'37 of v37 ofk relay T. Thegbraking bars willtherezfore remain in their non-braking positions.

When the first wheel of the car passes the treadles 28T1 and 28e, the operation of the apparatus will be similar to its operation when this car wheel was passing the treadle 28C. That is to say, relays Td and VTe will become energized and will complete theirV stick circuits, and relays T1 and T'c will become deenergized dueto their stick circuits being-interrupted yat contacts 291and 29e, respectivel Y v .ySometiIne after the first wheel of the car passes treadle 281b` and before itpassesltreadle 28f, the.' second wheel of 'the car will pass treadle'28, it being apparent that treadle 28a will not become depressed while treadle128b is.` still depressed, and thattreadle 28C will returnwto its normal position before treadle 28a returns toits normal position, because, as previouslypointed out,`the distance from the entering end of'one treadle to the leaving end of the treadlevnext in advance is less thanthe distance between adj acentv wheels on the same truckfofa car, and thedistance from the entering' end'of'one treadle to the leaving end of the second'treadle inadvance is vgreater than'the distance between adjacent car wheels on .the sametruck of ancar. Duev to thefsecond wheel .passing-treadle 28a, relay lIFwill again pickup andwill close its stick circuitinthe manfneripreviously described so that .acircuit` for relay C will again become completed atfrontcontact 37' of rel'ay'- Ta.

When the:Y first wheel `of the car passes treadle128f', .the resultant opening ofY contact 29f4 will interrupt the stick circuits for relays Ti'and Tsothat both of these frelayswill become deenergized,.butsince relay TF is now energized, relay C will remain energized.

Asthe other wheels of the car successively operate the treadles 28, the relays Twill become Aenergized and deenergized .in the `same mane-rzasiwhen the first wheel-'operated these treadles,.there being no time during which all of: these relays. are deenergized until lthe car has reached the position in which the last wheel depresses treadle 28f. Whenthis happens, the subsequent :deenergization of relays T'and Te `will deenergize relay C, and the brakingybarshwill then be restored to their braking positions.

- It *willv be seen, therefore, from the foregoinggthat when a car which is travelling at a" speed which is lless than control speed traversesthe stretch of track shown in the draw.-

I ing, the braking bars of lthe retarder R'will move to their non-braking positions as soon as the firstwhcel'of ythe car passes Vtreadle 28a and'V will subsequently remain in their non brak-ing,positions until the last'3 wheel of theTV car has depressed treadle28f. As a. result, no

Yretardation of the 4car willtake place under these conditions. a

I will now assume that with the braking v .a speedwhichis less than Vthis control speed,

and that before the car has entirely departed from the stretch, the car accelerates to a speed which is greater than thiscontrol speed. Under these conditions, as long as the speed of the car remains belowr control speed, the apparatus willfunctionin the manner previously described.V As soon, however, as the car attains a speed whichis above control speed, anyof the treadles 28 which subsequently becomes depressed by the wheels of the car will not remain depressed for a sufficient interval of time to permit the associated relay S to release,and as a result, when the car has moved far enough to depress the treadle which controlsl the'stickcircuit for the relay T which last became energized', this relay will become deenergized and will deenergize relay C. .Vhen this happens, the braking bars will moveto their braking positions, andfwill start to slow-down the car. Forexample, I will assume that the car speeds up to azspeed which is above control speed just as the forwardy wheel of the car moves into engagement with treadle 28, so that relay Sc will not release. Under these conditions, as long as the forward wheel remains in engagement with' treadle28c, relay T", which became energized whilethe forward wheel was passing treadle 28h, will be held energized by virtueof its stick circuit, and relay@ will therefore also be energized so that the braking bars will occupy their non-brakingr positions. All ofthe other relays T will be deenergized. As soon, however, as the forward wheel'of the car depresses treadle 28, Vthe stick circuitfor relay Tb will become interrupted, and relay Tb will therefore become deenergized. When relay Tb becomes deenergized, since all .of therother relays T5 are then deenergized, relay C will also become deenergized, and the braking bars will therefore be moved to their brakingpositions in the manner previously described.

After the braking bars have been moved to their braking positions due to the car haV- ing accelerated to a speed'which is above control speed, as just described, the braking bars will remain in their braking positions until the car hasdeparted entirely from the stretch, unless the car is againslowed down bythe retarder to a speedv which' is below lcontrol speed. If this happens, then as soonY thereafter as a wheel ofthe caripasses one of the treadles. 28,' there-lay S control-led thereby will closekits back Contact whiclnin turn, will energize .the' associated relay* AsV a result, relay CWillagain become energized and Will cause the braking bars to return Yto their non-braking positions. i i It, With the braking bars in their braking positions an'divithrheostat D-set for the relays S to release at a particular control speed, a car enters the stretch otrack shown in the drawing at a speed Which is greater than this control speed,'the braking barsy Will remain in their braking posit-ions until thel cari has been slowed dovvn tothis control speed. When this happens, thev braking bars Will then be automatically moved totheir non! braking positions in amanner which will be apparent from the foregoing.' l "Y t will be seen, therefore, that-*With a car retarder constructed in accordance with my invention, the braking action of'theretarder Will be automatically controlledvin accordance with the speed or" theA carin such manf ner that the car Will leave the retarder at aV speed which depends` upon the vsetting of rheostat D; I j

One feature of carreta'rder' controlling apparatus embodying my invention isthat the greater part of the apparatus employed is ci' standard construction Which greatly reduces the cost of installation. Y l f ,Y

Another feature of car retarder controlling apparatus embodying my invention is'that it is simplein operation and requires substan- Y tially no maintenance.`

Still another advantage of car retarder controlling apparatus embodying lmy invention is that accurate spacing of the treadles which operate the contacts 29 is unnecessary,

and a very simple type oi'treadle may beV employed. r v

Although I have herein shown and described only one form of car retarder con-V trolling apparatus embodying my invention,

it is understood that various changes and modiiications mayV be made therein `Within the scope of the appended claims Withoutdeparting from the spirit and scope of my invention.

Having thus described my invention, What l claim is: j

l. In combination, a stretch of railway track, a braking bar located adjacent one of the rails of said stretch and movable into engagement with a part of a car traversing said stretch for retarding the speed of the car, a series of contacts arranged to be successively operated by a car traversing said stretch, a series of timing relays one controlled by each contact of the series but the last, a series of locking relays one controlled by each of said timing relays and by a contact of the series located in advance of the contact which controls the associated timing relay, and means controlled'by said locking relays for controlling said braking bar.

2. In combination, a stretch or railway track, a braking bar located adjacent one of the vrails of said stretch and movable into engagement vvith a Vpart of a car traversing said stretch for retardingthe'speed of the car, a series of contacts arranged to be successively operated by a car traversing saidV stretch, a series of timing relays one controlled by each'contact of the series but the last, a series of locking relays one controlled by each of said timing relays and by a contact of the series located in advance of the contact Which controls the associated timing relay,a control relay, meansy controlled by said locking relays for controlling said control relay, and means controlled by said con- Y trol relay for cont-rolling said braking bar. 3*. In Vcombination, a stretch of railway track, a braking bar located adjacent one of the vrails of said stretch and movable into 'i engagementvvith aV partvof a car-traversing said stretch for retarding the speed of-the car, a series of contacts arranged to be successively operated byV a car traversing said" stretch, aseries of timing relays one controlled by each contact of the series but the last, a series ot locking relays one controlled by each of said timing relays and by a contact of the series located in advance of the contact Which controls the associated timing relay,a manually operable device, and means controlled by said locking relays and by saidmanually operable device for controllingsaid braking bar.

a. In combination, a stretch of railway track, a braking bar located adjacent one of the rails of said-stretch and movable into engagement with a part of a car traversing said,

control relay and by said manually operable'` device Vfor controlling said braking bar.

5. ln combination, a stretch of railway track, a braking bar located adjacent one or' the rails of said stretch and movable into engagement With a part of a car traversing said stretch for retardingthe speed of the car, a series of contactsl arranged to be suc-` cessively operated by a car traversing said stretch, a seriesof timing relays one controlled by each contact of the series but the last, means for lvarying the operating characteristics of all of Vsaid timing relays simul-y taneously, a series of locking relays onecontrolled by each of said timing relays and by al contact of the series located in advance of 'the' contact which controls the associated timl ingjrelay,and means controlled by said lock-l ing relays for controlling said braking bar.

6. In combination, a stretch of railway track, a braking bar located adjacent one of the rails of said stretch and movable into engagement with a part ofa car traversing said stretch for retarding the speed of the car, a

the contact which controls the associated timing relay, and means controlled vby said lockingrelays for controlling said braking bar.

VY. Inj combination, a stretch kof railway traclnabraking bar located adjacent one of the railsofsaid stretch and movable into engagement with part of a car traversing said stretch for retarding the speed of the car, a seriesot contacts arranged to be successively operated by a car traversing said stretch, a series of timing relays one-controlled by eachcontact of the series but the last, 'a series of locking vrelays oneassociated `with each of said timingfrelays and each provided with a pick-up circuit which is Vcontrolled by a contact of the associated timing relay, astick circuit for each of said rlocking relays controlled by its own front contact and by a'contact of said series located in advance of Ythe contact which controlsjthe asf sociated timing relay, and means controlled by said locking. relays for controlling said braking bar. s

8.` In combination. a stretch ot railway track, abraking bar located adjacent one of the rails of said stretch and movable into'enj gagementwith the wheels of a car traversing said stretch for retarding the speed of the car; a lirst, a second, and a third contact arranged to be successively. operated as the car traverses said stretch, a first timing relay controlled by said first contact and a secondv timing relay controlled by said second con' tact, a rst and a second locking relay, a pickup circuit lio-r said iirst locking relay controlled by a contact of said first timing relay, a stick circuit for said i'irst timing relay controlled by controlled bysaid locking relays for controlling said braking bar. i n Y 9. In combination, a stretch of railway track, a braking bar located adjacent one of the rails of said stretch and movable into engagement with a car traversing said stretch for `retarding the speed 'of the car, a series eratedby acartraversing"saidrstretcln a se ries of timingv relays'one controlled by each contact of the series but the last, a series of locking relays one .associated witheach of said timing relays rand each provided with a Y pick-up circuit which is controlled by a contact fof the associated timing relay, a stick circuit for` each locking relay but lthe last lockingl relay of the series of each said stick circuit including a front contact of the associated locking relayand the second contact of the series in radvance of the one which' controls the timing relay which controls such associated locking relay, a stick circuit for said last locking relay including .its own f front contact and the last contact of rthe series of contacts,and means controlled by said timing relays for controlling said braking bar.

V10. In combination, a stretch ofi-railway track, acar retarder Vassociated with said` stretch, a series of treadles located adjacent one of the rails of said stretchin positions wherethey will be successively engaged and depressed by each wheel of a car traversing such one rail, aseries of normally closed contacts one controlled by each of said treadles, a series orf-slow releasing'timing relays one controlled by each contact of the series but the last, a series of locking relays one associated with each of said timing relays and each provided with a pick-up circuit which` is controlled by a back contact of the associated timing relay, a stick circuit for each locking relay `ofthe series but the last, each said stick circuit including a'front contact of theassociated locking relay and the second contact of the series of contacts in advance of the contact which controls the associated timing relay, a stick circuit for the last locking relay of the series including its own front contact-and the last contact of the series of contacts, a control relay, a plurality of circuits for said contro-l relay one controlled by a front contact of each of said locking relays, and means controlled by said ontrol relayl for controlling said braking In testimony whereof I aHiX my signature.

'JOHN W. LIVINGSTON.

of contacts arranged to be successively 0p- "rtl 

